Washer Method: R is region bounded by ? = 3??^(−0.02?^2) and the ?-axis

[fivestar]

Washer Method: R is region bounded by ? = 3??^(−0.02?^2) and the ?-axis

Let ? be the region bounded by the graphs of ? = 3??^(−0.02?^2)
and the ?-axis on the interval
[0,15]. Set up, but do not evaluate, a definite integral which represents the volume of the solid obtained
when ? is revolved around the line ? = −2.

I am doing the washer method, but im not sure how to find the length of the both radius.

 

[Deleted member 4993]

Let ? be the region bounded by the graphs of ? = 3??^(−0.02?^2)
and the ?-axis on the interval
[0,15]. Set up, but do not evaluate, a definite integral which represents the volume of the solid obtained
when ? is revolved around the line ? = −2.

I am doing the washer method, but im not sure how to find the length of the both radius.

For these types of problems. start with sketching the function (using wolframalpha.com):